The invention relates to a bridge laying apparatus comprising a vehicle with devices for supporting at least two bridge sections composable into a bridge and being superimposed during transport, as well as devices for the composition and laying of the bridge, wherein the bridge tracks are connected to one another via crossbeams and the laying apparatus is arranged and guided between these bridge tracks.
A bridge laying apparatus has been known (DAS [German Published Appliction] 1,658,604) exhibiting a telescopic supporting arm extensible in the longitudinal direction of the bridge, this arm being arranged between the bridge tracks, the bridge being displaceably supported on this arm. This support is pivotably articulated to the vehicle and has a projection at the free support end serving for laying the bridge and being in engagement with the bridge during this procedure. After termination of the laying process, the extensible parts of the supporting arm are again telescoped inwardly. Such a device is expensive from a constructional viewpoint and heavy for the laying of bridges having relatively large lengths, since the supporting arm must in each case exhibit the length of the bridge to be laid, which requires, in case of long bridges, a large number of telescoping strokes as well as control devices for retraction and extension. Besides, a relatively long telescoping cantilever arm tends to sag considerably, which substantially impairs the function of the support during laying. Such a laying system with a telescoping supporting arm is provided furthermore only for laying one bridge length or one type of bridge, which extensively reduces the usage possibilities for such a device.
It is an object of the invention to provide, as contrasted to the above, a bridge laying apparatus eliminating these disadvantages and being usable for the laying of differing types of bridges and bridge lengths, and which consequently can be adapted to various utilizations.
This object has been attained in accordance with a preferred embodiment of the invention by providing that a laying beam with a launching girder partially embedded therein constitutes the laying device, the latter being longitudinally displaceably supported, via a guide means, at the vehicle as well as the crossbeam and being equipped with roller pairs arranged on the side of the bridge and mounted on both sides of the launching girder, respectively one of the rollers of these roller pairs serving for the guidance and support of the bridge on the laying beam and the further roller serving for the guidance and support of the launching girder in the bridge.
Furthermore, provision is made according to an aspect of the invention to support the laying beam on a guide arm articulate on the side of the vehicle, this guide arm carrying the guide means of the laying beam and comprising rollers running on both sides of the beam in guide tracks. In particular, the guide arm is pivotably articulated in the forward region of the vehicle about a horizontal axis and can be adjusted to high and low levels via a hydraulic cylinder, wherein the laying beam has a U-shaped profile open toward the topside of the bridge. The launching girder is held at the crossbeam in the hollow space of the profile, surrounded by the sidewalls of the beam. To extend the launching girder and for the displacement of the bridge, a worm and nut drive mechanism as well as a chain drive mechanism are provided in the laying beam. To connect the launching girder with the laying beam, the laying beam has on its end facing the end of the launching girder a gripping device establishing a rigid connection in the longitudinal direction of the bridge. This gripping device comprises a spring-loaded catch hook as well as a correspondingly fashioned opening in the launching girder for receiving the catch hook.
Still further, provision is made according to another aspect of the invention to provide the launching girder with a launching girder tip at its free forward end consisting of a controllable hydraulic cylinder privotably mounted to the girder, and a sole plate facing the terrain.
By means of the invention, a bridge laying apparatus has been created which is composed of a small number of constructionally simple and lightweight components, wherein these components in total result in a system which can be varied in dependence on the particular application. Thus, it is possible, for example, to lay without any problems various types of bridges, as well as bridges of varying lengths, within a minimum period of time. The laying of short bridges does not require a launching girder; the latter becomes necessary only if bridges of a relatively large length are to be laid. Since this launching girder remains in the thus-installed bridge, it is also possible without any complicated alterations to disassemble such bridge, as well as to lay bridges of varying lengths in succession. Furthermore, the laying apparatus is equally well suitable for caterpillar vehicles as well as wheel-type vehicles. Due to the fact that the launching girder remains in the laid bridge, a central cover is provided for the two lanes joined by way of crossbeams, resulting in additional safety for vehicle and personnel.
These and further objects, features and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, a single embodiment accordance with the present invention.